www.LinuxHowtos.org howtos, tips&tricks and tutorials for linux
from small one page howto to huge articles all in one place

search text in:

Poll
Which screen resolution do you use?

poll results

using iotop to find disk usage hogs

using iotop to find disk usage hogs

words:

887

views:

95882

userrating:

average rating: 1.7 (83 votes) (1=very good 6=terrible)

May 25th. 2007:
Words

486

Views

211334

Workaround and fixes for the current Core Dump Handling vulnerability affected kernels

Workaround and fixes for the current Core Dump Handling vulnerability affected kernels

words:

161

views:

92737

userrating:

average rating: 1.3 (28 votes) (1=very good 6=terrible)

April, 26th. 2006:

You are here: manpages

# LDEXP

Section: Linux Programmer's Manual (3)
Updated: 2015-03-02

## NAME

ldexp, ldexpf, ldexpl - multiply floating-point number by integral power of 2

## SYNOPSIS

```#include <math.h>

double ldexp(double x, int exp);

float ldexpf(float x, int exp);

long double ldexpl(long double x, int exp);
```

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

ldexpf(), ldexpl():

_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or cc -std=c99

## DESCRIPTION

The ldexp() function returns the result of multiplying the floating-point number x by 2 raised to the power exp.

## RETURN VALUE

On success, these functions return x * (2^exp).

If exp is zero, then x is returned.

If x is a NaN, a NaN is returned.

If x is positive infinity (negative infinity), positive infinity (negative infinity) is returned.

If the result underflows, a range error occurs, and zero is returned.

If the result overflows, a range error occurs, and the functions return HUGE_VAL, HUGE_VALF, or HUGE_VALL, respectively, with a sign the same as x.

## ERRORS

See math_error(7) for information on how to determine whether an error has occurred when calling these functions.

The following errors can occur:

Range error, overflow
errno is set to ERANGE. An overflow floating-point exception (FE_OVERFLOW) is raised.
Range error, underflow
errno is set to ERANGE. An underflow floating-point exception (FE_UNDERFLOW) is raised.

## ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).
 Interface Attribute Value ldexp(), ldexpf(), ldexpl() Thread safety MT-Safe

## CONFORMING TO

C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD, C89.

frexp(3), modf(3), scalbln(3)

## Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUE
ERRORS
ATTRIBUTES
CONFORMING TO
COLOPHON

Other free services
toURL.org
Shorten long
URLs to short
http://tourl.org/2
tourl.org
.
Reverse DNS lookup
Find out which hostname(s)
resolve to a
given IP or other hostnames for the server
www.reversednslookup.org
| |